Autonomous vehicles use various computing systems to aid in the transport of passengers from one location to another. Some autonomous vehicles may require an initial input or continuous input from an operator, such as a pilot, driver, or passenger. Other autonomous systems, for example autopilot systems, may be used only when the system has been engaged, which permits the operator to switch from a manual mode (where the operator exercises a high degree of control over the movement of the vehicle) to an autonomous mode (where the vehicle essentially drives itself) to modes that lie somewhere in between.
In some situations, the autonomous vehicle may require the driver to take control of some aspect of control, such as during heavy traffic, poor sensor conditions, etc. When the driver in an autonomous vehicle is prompted to take control there is an immediate need to establish if the driver has actually done so satisfactorily. For example, it may be very unsafe for the autonomous components to make the assumption that simply because the driver was alerted to take control that he did. If the driver did not, the vehicle could disengage from the task of maneuvering the vehicle and possibly cause an accident. Various systems use different transition or hand-off confirmation methods. For example, requiring the driver to push a button upon transition might constitute a satisfactory hand-off. Some systems may engage in an autonomous mode as soon as the vehicle detects that the driver releases the steering wheel suing, for example, a force sensor added to the steering wheel, steering column, etc.